Numbers 16:39-40

39So Eleazar the priest took the bronze censers presented by those who had been burned up, and they were hammered out as a covering for the altar.

40It was a memorial for the Israelites, that no outsider who is not a descendant of Aaron should approach to burn incense before the Lord, that he might not become like Korah and his company – just as the Lord had spoken by the authority of Moses.